Some Littoral Mites of Millport. 137 
a helpless way when touched, till 10 A.M. on 26th July, when it was released. 
Another specimen isolated under the same conditions, also for forty-eight 
hours, gave the same result. The mite when released was lethargic in each 
case. 
It is evident, then, that Halolelaps can endure complete immersion for at 
least forty-eight hours, but that during this time it is not living the life of 
an aquatic organism, but is merely exhibiting what Plateau (1890, p. 268) 
noticed as ‘‘a general property of abranchiate Arthropods, which all, or 
almost all, resist asphyxia for a remarkably long time.” 
The facts to which attention is called in this particular case are the 
presence of air in the peritreme tube of the mite, and the possibility under 
the ordinary conditions of its life of its finding, during the hours of tidal 
submergence, a reservoir of air in the crevices of the stones or amongst the 
encrusting organisms of its habitat. 
DIAGNOSIS OF THE SPECIES. 
Translated from A. Berlese, 1905, p. 109. 
Gamasus (Halolcelaps) glabriusculus, Berl. et Trouess. 
1% Gamasus marimus, Brady, 1875. 
Halolelaps glabriusculus, A. Berlese et Trouessart, Diagnoses d’Acariens nouveaux 
ou peu connus, 1889. 
Zercon marinus, Moniez, Acar. et ins, marins des Cotes Boulonnais, 1890. 
Colour, brownish-golden; ovate, scarcely shouldered, rounded behind. 
Integument quite conspicuously areolate. Body-hairs very short (except some 
of the posterior ones, especially an unpaired postanal one), subspiniform, few. 
Male with the legs of the second and third (pairs) scarcely thicker than the 
others, furnished with spurs, Femur of the second pair with a conical spur below 
(which is) short and directed outwards, also a rather strong spine; genu and tibia 
unarmed ; tarsus with below two equal conical spurs, (which are) subacute at their 
apex. Femur of the third pair with a short spur below, (which is) conical, acute ; 
genu with a rather strong process below under its apex, the rest of the same genu 
faintly roughened with tubercles below ; tibia unarmed ; tarsus armed, in the 
middle of its side, with a rather large, weak tooth. Femur of the first pair armed 
below, almost at its base, with a stout hooked tooth directed forwards. Epistoma 
in either sex well chitinized, rounded in front and deeply and irregularly serrulate 
on its whole anterior margin with numerous small teeth. Chela of the male very 
small, slender, with weak digits distinctly hooked at their apex: fixed digit 
straight, the more slender, almost entirely toothless, but armed in the anterior 
third part of the dentarial margin with two quite large teeth; movable digit 
slender, but quite broad at its base, with a single rather large tooth beneath the 
hook: calear narrow, standing well out from the inner base of the movable digit, 
at first folded inwards, then directed outwards, and finally reaching the top of the 
costula. Chela of the female with subequal digits, the fixed one with quite 
vestigial teeth on about half the dentarial margin, five or four in number ; 
movable digit almost similar but with the teeth more conspicuous. Epigynium 
